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The orbit bump technique has been used at the ALBA Storage Ring to characterize with good precision the impedance of single machine elements, like the in-vacuum undulators or the CLIC stripline kicker. The results are compared with theoretical studies, as well as impedance measurements done at ALBA using other methods like the turn by turn betatron phase or from the analysis of the detuning slopes of the Transverse Mode Coupling Instability., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

ALBA has started a study that will produce the design of a new lattice for a diffraction limited photon source. The baseline lattice should preserve the present circumference and energy, and keep the insertion device beamline source points as much as possible unchanged. The first solution is a 16-fold periodic ring based on a 7BA cell with dispersion bump, paired sextupoles and anti-bends. An emittance of 155 pm·rad would be reached without longitudinal gradient in the dipole magnets., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

The non-invasive diagnostics in the ALBA Booster-to-Storage (BTS) transfer consist of Beam Position Monitors (BPM) and Synchrotron Radiation Monitors (SRM), which together provide position, size and shape of the beam. However, they were not reliable enough for a systematic improvement of the transfer efficiency in the BTS, which has been fluctuating since day one. In order to optimize it, two major upgradse have been performed: first, the BPM electronics have been upgraded for single-pass beam detection, showing a factor 10 better position resolution than the former units. Secondly, the SRMs mechanics and automation were significantly improved to provide a more robust optics alignment. Both BPMs and SRMs are now routinely used to keep transmission efficiency along the BTS constant over weeks., Proceedings of the 6th Int. Beam Instrumentation Conf., IBIC2017, Grand Rapids, MI, USA

Injection into the ALBA storage ring presently uses a conventional local injection bump with four dipole kickers. However, following the promising results of the first tests with single multipole kicker injection at other light sources, studies to implement this new injection scheme have been started for ALBA. Two possible designs for the kicker have been considered: a pure octupole and a non-linear magnet similar to the BESSY type. A comparison between the expected performances of the two kicker designs has been carried out in terms of injection efficiency and transparency for the users. This paper summarises the beam dynamics results from multi-particle tracking simulations and the proposed kicker magnet design., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

A novel method to perform Beam Based Alignment has been tested at ALBA using the 10kHz fast acquisition BPMs together with an AC excitation of the corrector magnets allowing to speed up the beam based alignment process. The former approach relies on software synchronization and tango device servers to execute a series of DC corrector magnets and quadrupoles settings designed to avoid the quadrupole hysteresis effects. The approach that we present here is simpler, gives the same level of accuracy and precision and speeds up the measurement by a factor 10. The total measurement time has changed from 5 hours to 10 minutes., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

At ALBA the standard orbit response matrix measurement with DC corrector magnet (CM) modulation is being upgraded with an AC excitation of the correctors combined with the synchronized beam position monitor (BPM) acquisition data rate at 10 kHz. Several types of excitation waveforms (sinusoidal vs square types) and frequencies have been tested and compared to optimize the measurement precision and repeatability. The data acquisition time of the ALBA response matrix (88 horizontal and 88 vertical correctors) with the new AC method takes 1 minute to complete instead of 7 minutes of the standard technique., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The ALBA insertion device beamlines have a horizontal and vertical rms source size of 130 and 5.5 microns. Protein crystallography beamlines (Xaloc) would benefit from a reduction of the horizontal and increase of the vertical beam size, to gain spatial resolution and avoid anisotropy effects. A modified lattice with horizontal and vertical beam size of 74 and 9 microns has been setup and tested, breaking the ring symmetry, with different setting of the six neightbouring quadrupoles at each side of the Xaloc insertion device. Such configuration keeps the nominal emittance almost unvaried and the working point is recovered by small changes in the quadrupole strengths of the four symmetric matching sections. A dedicated setting of the nine available sextupole families has been obtained by numerical optimization of the dynamical apertures and tune shifts. The lattice settings have been satisfactorily tested. The measured lifetime is reduced a factor two and the injection efficiency decreases to 60%. Finally, the option of increasing the number of sextupole families, to recover the dynamic aperture and guarantee the injection efficiency, has been studied., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

A transverse impedance source manifests itself, among other ways, by producing a small defocusing kick which depends on the beam bunch charge. By repeating optics measurements for different bunch charges, it is possible to disentangle the contribution produced by each impedance source from the dominating focusing effects given by the machine optics. But hunting for such faint defocusing effects poses strong requirements on the precision and sensibility of the measurements, and slow machine drifts or different thermal conditions shall be avoided. In this report, we present a novel method to assess in a fast and precise manner machine optics for different bunch charges using BPM turn-by-turn data and hybrid filling patterns. Finally, measurements for different ALBA machine components like scrapers and In-vacuum undulators are compared with simulation results., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

The N-BPM method recently developed for the LHC has significantly improved the precision of optics measurements which are based on beam position monitor (BPM) turn-by-turn data. The main improvement is owed to the consideration of correlations for statistical and systematic error sources, as well as increasing the amount of BPM combinations for one measurement. We present how this technique can be applied at light sources like ALBA, and compare the results with other methods., Proceedings of the 6th Int. Particle Accelerator Conf., IPAC2015, Richmond, VA, USA

Turn-by-turn measurements paves the way for fast storage ring diagnostics. On the other hand turn-by-turn technique is by its very nature delicate, requiring an extensive system tuning and understanding. During last year several attempts to recover linear model informations from turn-by-turn measurements has been carried out in cooperation between the synchrotrons of SOLEIL and ALBA. A routine to extract phase advance and betatron amplitude from turn-by-turn measurements in presence of damping has been developed. Moreover a procedure to retrieve quadrupole errors from such observables has been developed tested and verified against the traditional diagnostics tools based on closed orbit measurements. A comparison between the different methods and the performance of the two different experimental setups are reported., Proceedings of the 6th Int. Particle Accelerator Conf., IPAC2015, Richmond, VA, USA

A proposal of a low alpha lattice for the ALBA third generation light source is presented. Opposed to most of other machines, belonging to the same category, ALBA employs an optimized lattice making use of combined function dipoles. This has permitted a very compact design stripped out of all not strictly necessary quadrupoles resulting in a lack of flexibility. For such a reason the common approaches used in many other synchrotrons can not be directly applied to ALBA and a different strategy has to worked out., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

This paper summarizes the tasks carried out to develop a turn-by-turn (TBT) measurement system at ALBA. These tasks mainly include testing the MAF firmware for the libera BPMs and implementing the necessary analytical tools to infer the beam dynamics parameters. TBT measurements using an injection kicker are presented. Linear and non-linear beam dynamics results are compared with LOCO. Results are still preliminary since a good agreement with the linear model has not been achieved yet., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The ALBA light source has been operating in decay mode since May 2012. Now it is ready for top-up operation, which should become the standard operation mode for users from mid 2014. In this paper we are going to summarise the different steps that have taken place before the start of top-up operation: radiation safety simulations and measurements, upgrade of hardware and software interlocks, control software and injection optimisation., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The synchrotron light source ALBA incorporates 6 insertion devices (2 Apple-II type undulators, 2 plannar in-vacuum undulators, 1 normal conducting multipole wiggler and 1 superconduction multipole wiggler) at the start of operation. The effect of the different IDs in the performance of the facility is evaluated, using several methods (kick maps, hard edge models, dynamic multipoles, …), including a comparison of the agreement of the different models and simulation codes. According to the results, and due mainly to the influence of the superconducting wiggler, a new working point has been selected., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The high order magnetic multipole components of all the magnets in the ALBA storage ring have been measured. Previous studies have simulated the effects of the HOMs using statistic methods. The magnets have been installed now in the tunnel, allowing for a better simulation of the future impact of the HOMs in the performance of the light source. In this paper, the effect of the high order multipoles of the dipole, quadrupole and sextupole magnets in the dynamic aperture and the Touschek lifetime are reviewed., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The commissioning of the booster for the synchrotron light source ALBA should take place in the period December 2009-January 2010. In this paper, the beam dynamics aspects of the commissioning are described, including the studies performed, the main problems find during the commissioning and a comparison of the measured beam parameters to the design one. A description of the software tools used and developed for the task is included., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

A pinger magnet system consisting of two short kickers, one for each transversal plane, has been recently commissioned at the ALBA Synchrotron Light Source. The kickers can excite large betatron oscillations on the electron beam in order to probe the linear and non-linear beam dynamics regime together with the turn-by turn capabilities of the BPMs. The kickers are mounted in a single Ti coated ceramic vacuum chamber, have a length of 0.3 m each and provide a half sine pulse with a pulse length of 1 μs at an amplitude of 1.4 mrad and the pulser unit is based on solid state technology. This report summarises the steps followed from its design until its installation, electric and magnetic characterisation in the laboratory, and the first results with beam., Proceedings of the 6th Int. Particle Accelerator Conf., IPAC2015, Richmond, VA, USA

LBA es una fuente de luz de sincrotrón de tercera generación, en funcionamiento desde 2011, al servicio de una comunidad científica e industrial nacional e internacional. Varios laboratorios (lineas de luz) explotan la radiación electromagnética hasta los rayos X, para una amplia gama de experimentos físicos, químicos, y biológicos. Con el fin de conseguir un elevado flujo de radiación y pequeña divergencia, el anillo de almacenamiento de electrones emplea imanes intensos distribuidos en una malla optimizada para dar forma a las características del haz de electrones. Por otra parte, los imanes pueden tener varios errores qué afectan, de forma perjudicial, a las características del haz de electrones tales como el tamaño, la divergencia o el tiempo de vida. Los errores pueden ser debidos a tolerancias de fabricación mecánica, histéresis magnética, variaciones térmicas o desalineaciones mecánicas. El delicado "equilibrio magnético" requerido para operar éstas fuentes de luz no podría cumplirse sin una herramienta para medir y corregir la malla magnética. Para este propósito, han sido desarrollados procedimientos que utilizan el haz almacenado como sonda para inspeccionar los campos magnéticos reales. Entre las distintas técnicas, las medidas "vuelta-vuelta" permiten construir un modelo de los errores magnéticos a través de la observación del movimiento transversal del haz de electrones vuelta tras vuelta. El objetivo principal de esta tesis doctoral es implementar por primera vez la técnica vuelta-vuelta en ALBA a fin de establecer las capacidades de las medidas de errores magneticos lineales y no lineales. Un primer conjunto de experimentos está dedicado a la caracterización de los errores lineales que muestra un nivel de acuerdo (beta-beat < 2%) comparable con el de otros métodos basados en medidas de órbita cerrada. Pruebas adicionales para establecer la máxima sensibilidad a pequeñas variaciónes de las funciones ópticas se has obtenido manipulando elementos magnéticos y midiendo las variaciones ópticas producidas. La técnica vuelta-vuelta se ha aplicado también a la caracterización del acoplamiento de betatrón en ALBA. Se ha observado un alto grado de precisión en la localización de la fuente de error, y sólo un 10% de desacuerdo entre las medidas de la fuerza de la fuente de acoplamiento y las predicciones teóricas. Una prueba similar también se ha llevado a cabo para las familias de sextupolos, utilizando uno shunt resistivo para cambiar de manera individual la corriente de excitación de un sextupolo. La capacidad de localizar la posición del error sextupolar ha sido demostrada con éxito. Los experimentos mostraron cómo la técnica vuelta-vuelta destaca por sensibilidad a pequeñas variaciones de las funciones ópticas. Esto hizo posible, por primera vez en una fuente de luz de sincrotrón, la aplicación de la técnica vuelta-vuelta a la medida de fuentes localizadas de impedancia transversal. El experimento, llevado a cabo en ALBA, ha permitido distinguir y caracterizar el efecto de desfocalización producido por diferentes fuentes de impedancia transversal, incluyendo elementos como el scraper, cámara de vacío de los imanes de inyección o de un ondulador y la cámara de vacío estándar. La buena concordancia entre medidas y modelo de impedancia transversal, basado en el cálculo analítico de la pared resistiva y en la simulación del código GdfidL de la impedancia geométrica, ha confirmado que la técnica vuelta-vuelta es una herramienta de diagnóstico muy sensible. Asimismo, se ha demostrado que fuentes de impedancia más pequeñas pueden ser caracterizadas adecuadamente variando la óptica de la máquina de modo de obtener una ampliación del efecto de desfocalización inducido. Este método se ha utilizado para caracterizar impedancias tan pequeñas como el de un "in vacuum undulator" de ALBA., ALBA is a third generation light source, commissioned in 2011, serving a national and international scientific and industrial community. It provides synchrotron radiation up to the hard x-rays as a tool to multiple laboratories (beamlines) for a wide range of physical, chemical, and biological experiments. In order to achieve the required radiation flux and small divergence, the electron storage ring employs an optimized design where strong magnets are combined in a rather complex lattice to properly shape the characteristics of the electron beam. However, the lattice can have several errors, which detrimentally affect the electron beam characteristics such as size, divergence, or lifetime. Unavoidable lattice errors can be due to manufacturing mechanical tolerances, magnet hysteresis, thermal variations and/or mechanical misalignments. The delicate "magnetic equilibrium" required to operate such light sources could be hardly met without a tool to measure and correct the actual magnetic lattice. For this purpose beam-based methods, where the stored beam serves as probe to inspect the lattice, have been developed. Among the various techniques, turn-by-turn measurements allow to asses a lattice error model by sampling turn after turn the transverse motion of the beam. The main purpose of this PhD work is to implement for the first time the turn-by-turn technique at ALBA in order to establish the capabilities of the measurements in the context of linear and non-linear lattice errors. A first set of experiments was dedicated to the characterization of the linear lattice, showing a level of agreement (beta-beat < 2%), comparable to what observed with other methods based on the closed orbit technique. Further tests to establish the ultimate sensitivity to small optical functions variations were obtained by manipulating single lattice elements and measuring the resulting optics variations. Turn-by-turn technique has been applied to the characterization of coupling in the ALBA light source. The ability of turn-by-turn to correctly localize a single source of coupling was challenged by introducing in the storage ring lattice a controlled coupling source. A high degree of precision was observed in localizing the error source, and only a 10% disagreement between measurements and theoretical predictions on the coupling source strength was observed. A similar test was also carried out for the sextupole families using a resistive shunt to change the excitation current of a single element. The ability to localize the sextupolar error position in the lattice was successfully demonstrated. The experiments showed how the turn-by-turn acquisitions shine as for sensibility, enabling the detection of very small variations of the optics function. This made it possible to apply the turn-by-turn technique, for the first time in a light source, to the measurement of localized transverse impedance sources. The experiment, carried out in the ALBA storage ring, led to the characterization of the individual defocusing effects produced by different transverse impedance sources, including elements like scraper, injection zone, in-vacuum undulator and standard vacuum beam pipe. The good agreement between the measurements and the transverse impedance model based on analytical calculation of the resistive wall and GdfidL simulation of the geometrical impedance confirmed that the turn-by-turn technique is a valid diagnostic tool to carry out very sensitive and non-intrusive optics measurements. Furthermore it has been shown how the smaller impedance sources can still be properly characterized by manipulating the machine optics in order to obtain a magnification of the induced defocusing kick. This method has been used to characterize impedances as small as the one of the ALBA IVUs.